Synthetic rubberlike materials



reamed Feb. 11, 19.41

v 2,231,623 SYNTHETIC unnmtmxs MATERIALS Great Britain No Drawing. Application July 5, 1939, Serial No.

' 282,942. In Great Britain .i'uly 6, 1938 10 Claims.

This invention relates to the manufacture of synthetic rubberlike materials and more particue larly to the interpolymerisation of butadiene- 1:3 and its homologues with acrylates.

This invention has as an object to devise a new method of manufacturing synthetic rubberlike materials. A further object is to provide new synthetic rubberlike materials. A. further object is to devise a method of manufacturing synthetic rubber-like materials which can be compounded and vulcanised to give products resembling vulcanised rubber, but having greater resistance to oils and solvent. Astill further object is to provide new synthetic rubberlike materials which can be compounded and vulcanised to give products resembling vulcanised rubber, but having greater resistance to oils and solvents. A still further object is to provide new materials resembling vulcanised rubber but havsembling vulcanised rubber, but having'greater resistance to oils and solvents.

Methyl homologues of butadiene-1z3 and other esters of B-(2-furyl)acrylate may be used wlth sistance to oils and solvents.

similar results. As methyl homologues of butadiene-1z3, we mention especially lsoprene and,

2:3-dimethylbutadiene-1:3. Methyl and ethyl esters of B-(Z-furyDacrylic acid. especially the former, are the most convenient esters to use for the purpose of obtaining economically good rubber-like materials of good to very good re- Esters other than methyl and ethyl may be used, especially the lower unsubstituted alkyl esters. Esters of other kinds than alkyl may also be used, for instance dlvidual compounds chosen, but in general more butadiene-1:3 or methylbutadiene-1z3 than ester is to be used.

The emulsions of the butadiene-1:3 or methylbutadiene-1z3 and ester may be made by agi- 5 tating them with water and an emulsifying agent. Frequentlythe emulsification and polymerisation -may be conveniently effected together, in what may be regarded as a single technical operation, if the ingredients of the mixture are emulsified 10 by agitating themat a temperature at which polymerisation takes place and then agitation continued long enough for the polymerisation to be effected. Cetyl p-dimethylaminobenzoate methosulphate is a suitable emulsifying agent to 15 use, but other salts derived from bases with long aliphatic chains and inorganic or organic acids, or salts derived from high molecular weight organic acids and inorganic bases may be used instead. Small proportions of one or more elec- 20 trolytes e. g., acetic acid or acetic acid mixed with sodium acetate may be conveniently used in the emulsion. Other ingredients may be included, namely agents which catalyse polymerisation, such as organic and inorganic peroxides, 25 and agents which modify or assist the course ,of the polymerisation, such as aliphatic compounds containing chlorine directly united to carbon, e. g'., carbon tetrachloride.

The products of polymerisation are produced 30 in latex-like form. They may be obtained in massive formby coagulating the latex, separating the coagulum, washing and drying. The

coagulation maybe effected by known methods,

e. g., by freezing, or by the addition of sodium chloride, sodium hydroxide, ethyl alcohol, or mixtures of these, depending upon the emulsifying agent, which has been employed. Washing and drying may be effected on heated rollers in a rubber roller mill which is furnished with a device for'washing, e. g., a water spray.

,3- 2-furyl) acrylic esters, may be made by esterifying ,a-(2-furyl)acrylic acid by the usual esterification methods.

The dry materials may be vulcanised by com- 4.5 pounding and heating, in a manner similar to that employed with natural rubber. Compounding may be eiiected with, for example, filling and reinforcing ingredients such as carbon black and zinc oxide, with or without sulphur and accelera- 50 tors. The cured products are better than vulcanised natural rubber in their resistance to oils and hydrocarbon solvents.

The resistance to oils and solvents depends upon the proportion of the ester incorporated in 55 the original monomer mixture. In general it is desirable to use at least 20% and preferably more than 30% based on the total polymerisable material present in order .to obtain a good resistance to oils and solvents. If more than 40% is em ployed the vulcanisate possesses a rather low resilience, ;but otherwise it is an excellent oil resisting product being practically unaffected by immersion in Diesel 011. We have also found that the products having the highest oil and solvent resistance are obtained by polymerisations, which are stopped short of very good yield. Thefollowing examples, in which parts areby weight, illustrate but do not-limit the invention.

Example 1 400 parts of water, 16 parts of cetyl P-dimethylaminobenzoate methosulphate, 22. parts Example 2 The rubberlike material obtained according to Example 1, is included in the following mixing:

Parts Rubberlike -material 100 Gas black 50 Zinc oxide 10 Stearic acid .-i 2 Mercaptobenzthiazole 1 Sulphur 2 Product of condensation .of. acetaldehyde' and aand B-naphthylamines according to British Specification 280,661 1 y The mix is cured for 60 minutes at 141 C. A

A tough resilient vulcanisate-is obtained, with good resistance to oils and solvents.

Ezcam ple 3 310 "partsof water, 106 parts of an aqueous paste containing 15% of sodium cetyl sulphate, .25 parts of methyl p-(2 -furyl) acrylate and50 parts of butadiene-123 are subjected to the polymerizing conditions described in Example 1.

A good yield of rubberlike material is obtained.

A similar product is obtained if isoprene is used instead of butadiene 1:3.

Example 4 If ethyl p-(2-furyl) acrylate is used instead of the corresponding methyl ester, in Example 1,, a very good yield of a similar rubberlike material is obtained. On compounding and vulcanizing this rubberlike material as in Example 2, aresilient vulcanizate is obtained, which has very good resistance to the swelling action -of oils and solvents.

Earample 5 If n-butyl p-(Z-furyll acrylate, (B. P. 146- 147/ 18 mm.) is used instead of the corresponding methyl ester in Example land 5 parts of carbon tetrachloride are also used in the poly-' merization mixture, a very good yield ofrubberlike material is obtained. The productwhen compoundedand vulcanized asdescribed in Example 2 gives a resilient oil-resisting material.

.ments of this invention may be made without ber of the group consisting of butadiene-1,3 and the rubberlike material thus obtained.

Example 6 The ester described in Example 5 is replaced by'fi-chloroethyl p-(2-fu'ryl) acrylate (B. P. 22 C./4 mm.). I 5

A very good yield of rubberlike product is obtained. When the product is compounded and vulcanized, as described in Example 2, it ieldsa vulcanisate, which is very resistant to oils and solvents.

Example 7 400 parts of water, 16 parts of cetyl p-dimethylaminobenzoate methosulphate, 22 parts of 6% acetic acid, 20 parts of carbon tetrachloride, 27.5. parts of methyl p-(Z-furyl) acrylate and 47 parts of butadiene-lz3 are subjected to the procedure described in Example 1.

A good yield of a rubberlike material is obtained, which after compounding and vulcanizing as described in Example 2 gives a vulcanisate which only swells to a small extent in oils.

A similar product is obtained if 2:3-dimethylbutadiene-1z3 is used instead of butadlene-1:3.

By using p-ethoxyethyl p-(2-furyl) acrylate (B. P. -141 C./4 mm.) instead of ethyl p- (2-furyl) acrylate in Example 5, a good yield of rubberlike product is obtained, and this when compounded and vulcanized as in Example 2 gives a good resilient oil-resisting vulcanisate.

If benzyl-p-(z-furyl) acrylate (B. P. 158+ C./3 mm.) is used instead of p-ethoxyethyl p-(Z-furyl) acrylate a. similar product is obtained.

As many apparently widely'diflerent embodideparting from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

We claim: 1. Process for the manufacture of new synthetic rubberlike materials which comprises polymerizing, in aqueous. emulsion, aniester of beta-(Z-furyl) acrylic acid together with a mem- 45 its methyl homologues.

2. Process for the manufacture of new syn- "thetic rubberlike materials which comprises polymerizi in aqueous emulsion, a lower unsubstituted alkyl ester of beta-(Z-furyl) acrylic 50 acid together with butadiene-1,3.

3: Process for the manufacture of new synthetic rubberlike materials which comprises polymerizing, in aqueous emulsion, methyl beta- (2-furyl) acrylate and bntadiene-IB.

4. Process for the manufacture of new synthetic rubberlike materials which comprises polymerizing, in aqueous emulsion, ethyl beta- (z-furyl) acrylate and butadiene-1,3.

5. An interpolymer of an ester of beta-(2- furyl) acrylic acid and a member of the group consisting of butadiene-1.3 and its methyl homologues.

6. An interpolymer of an ester of beta-(2- furyl) acrylic acid and a member of the gr'pup consisting of butadiene+1,3 and its methyl homologues. the latter material being present in larger amounts than the former material.

7. Process for the manufacture of .new synthetic rubberlike materials which comprises polymerizing, in aqueous emulsion, an ester of beta- (2-furyl) acrylic acid together with a member of the group consisting of buta diene-1,3 and its methyl homologues and compounding and curing 75 8. Process for the manufacture of new sYntained.

9. Cured synthetic rubberlike material where in the rubberlike inredient is an interpolymer 10 of an ester beta-(z-furyl) acrylic acid togather with a, member of the group consisting of butadiene-La and its methyl homologues.

iuryl) acrylic acid together with butadiene-1,3.

BERNARD JAMES HABGOOD. ROWLAND HILL. ELIAS ISAACS.

LESLIE BUDWORTH MORGAN. l0 

